Jointure for vulcanized-rubber parts



1. L.` MAHONEY.

JOINTURE FOR VULCANIZED RUBBER PARTS.

APPLICATION FILED :UNE 29,1918.

1,314,343. ,lzltvnlod Allg. 2G, 191).

4relates to 'jointnres of vulcanized rubber' l mined relationship in the positions of the -siding at New Haven, county of ,UNTTED sTATEs PATENT oEEIcE.

JEREMIAH L. MAHONEY, OF NEW HAVEN, CONNECTICUT, ASSIGNOR TO THE GOOD- YEARS INDIA RUBBER GLOVE MANUFACTURING COMPANY, A CORPORATION 0F CONNECTICUT.

lJOIN'I'URE FOB. VULCANIZED-RUBBER PARTS. i

Specification of Letters Patent.

Patented Aug. 26, 1919.

Original application led January 15, 1918, Serial No. 211,904. Divided and this application illed June 29,

' 191B. Serial No. 242,646.

To all whom t may concern Be it known that I, JEREMIAH L. MA- HoNEY, a citizen of the `United States, re-

New Haven, vState @f Connecticut,l have invented certain newand useful Improvements in Jointurs for' VulcanizedRubber Parts, of which thefollowing is a full, clear, and exact description. l

`This application is a division of my copending application Serial No. 211,904 and parts and has` for its principal object the Joining of rubber parts that have been previously vulcanized. p

A further object is to maintain, in the carrying out of my invention, a pre-deterjoined parts.

require less apparatus in making the jointures of the vulcanized rubber parts.

While my yinvention is not confined to any specific article ofy manufacture, it is however especially adapted for use in the manufacture of hollow rubber articles in which are formed temporary openings for the withdrawal therethrough of the forming lcores about which the articles are vulcanized and which openings must be subse` quen'tly, permanentl 1 closed to produce the finished articles. he invention is more especially directed to the manufacture of in the fillin hot water bottles and similar articles Where- 'of the with rawal of the core therefrom.

For convenience, and to facilitate a clear understanding of the advantages gained, my invention will therefore be described 'and illustrated in connection with the proneck is too small to permitv `descri ed, illustrated, and claimed.

Referring to the drawings forming pat of the specification l Figure 1 is a front View of. the lower mold section, and core.

.l Fig. 2 is a detail vertical central sectional view.

Fig. 3 is a sectional view taken on the line 3 3 of Fig. 1.

Fig. 4 is a front view of a closing mold section showing thebase of the bottle supported therein. v

Fig. 5 is an enlarged sectional view along the line 5-5 of Fig. 4.

Fig. 6 is a fragmental view of one half of the finished joint and,

Fig. 7 is a sectional view similar to Fig. 5 but showing a modification.

Hot water bottles of the type here referred 'to are usually formed from sheeted vulcanizable rubber cut or died out to form blanks of the desired patterns to form the several parts of the bottle, such for instanceV as the neck, tab and body portions. These are assembled in a `mold about a suitable core and vulcanized after which the core is withdrawn through a suitable opening and the opening finally closed. In the present instance, the blanks are cut from sheeted rubber stock to form the sides 1-1, the neck portion 2 and the tab 3. These are assembled in the mold sections 4-4 about a core 5 which has a removable portion for forming the neck 2 of the bottle which may be of any desired or well-known construction.

The core 5 is provided with a tongue 6 which protrudes through the base of the bottle and serves to maintain the edges separated during vulcanization of the bottle, in

order to provide an opening for finally yit portions is slightly thickened to provide a` correspondingly increased area for the abutting surfaces forming the joint. In the y present instance, I prefer to provide a still thicker portion along the bottom edges 8-8 about the slot 9 in order that a suiiiciently broad abutting joint may be subsequently l madel lwhen closing the slot to give the required strength thereto, as will later more fully. appear. AMoreover in the preferredV embodiment, the slot or opening 9 is formed .with more oI less rounding or V-shaped end portions which give further strength to the joint and the tongue 6 is conveniently Y formed to mold the slot With converging opposed Walls to form ythe V-shapedends.

'The Wall of the tongue 6 instrumental `in 4forming the opening may be of anyd'esired thickness and the outer `face of the margins about the openingmay beqin its original "shape slightly bulgedl outwardly so` that when the closure is eli'ecte'd the outer opposing surfaces of the margins about the opening will" be' brought to assume relative `positions corresponding to the relative positions of the margins about the remainder .I of the body portion of the bottle in order vto preserve uniformityof appearance about -the entire 'body of the bottle. In Fig; Q, 'this feature is shown by bulging the thickened portions v8-'-8 slightly outwardly so thaty when the slot 9 is closed these bulging faces v*willl be brought slightly closer togetherl tov correspond with the margins 'which were stance, ifonly rubber cement is to be used vulcanized together simultaneously with the vulcanization of the rubber material, conf stituting thebottle.l Of course,l in shaping the margins about the slot to produce the desired final result much will depend upon the quantity of vulcanizable rubber which is. to be' inserted iny the slot. For inthe bulged portions would be suflicient to approximately account for the thickness 0f the portion 6 forming the opening. While if a.

strip of vulcanizable rubber is used to form the closure, and tbe strip in its iinally compressed state be of substantially the thickness of the. tongue then little or no bulging would be necessary.

As my invention contemplates the closing of the opening by operations performed entirely from one side of the bottle and as it further contemplates the definite relative positioning of the parts about the opening, I provide a closing mold of special construction comprising the sections 1.0-10. The mold sections are provided with cavities 11-11 adapted to receive the portion of the bottle containing the slot or opening and to afford supporting' Walls to engage the parts to be joined from corresponding sides to accurately aline them with each other. It is of primary importance' that the joint be so nicely produced and theopposed parts so accurately register thatbesides giving the required strength to withstand the pressure test which the bottle must be subjected to, there Will be little or no manifestation of the existen-ce of a joint at this portion, in

'. order to make a readily salable article.

The joint forming the closure is usually made with the aid of pressure, previous to or during final vulcanization, and this pressure has a tendency to force the parts to be joined away from the exterior supportthat the opposing edges` will not accurately mg Wall provided by the mold sections so.

register in the filial product, thereby besides making a Weak joint also producing an unsightly and unsalable article. It is customarily the practice to provide an inte/l rior 4support pressing on the inner sides of the parts to be joined t0 insure a continual uniform pressure and positive registering of the opposed parts about theV opening or slot until the joint is finally set by vulcani- -zation. I accomplish this result by pull- 1ng,the parts, so to speak, against the /clos ing-mold?supporting-Walls instead of push- 165' ing the partsl as is the usual practice,

therebyobviating the necessity of.a second` core or inner support and the time and trouble of lplacing it in position and removing it from the neck of the bottle after the closure has been e'ected.

In order to produce the desired pull of the rubber parts, I placekthe vulcanized rubthe Walls of the slot -oropening opposed flanges 12-12 and place these under 'a tenfber abouti-he slot undertension in a direc tiontransversely-of the. slot, which tension. acts'to dra-W or pull and to vhold the rubber parts against their supporting walls.

sion during the closing or vulcanizing operation.' The tension is attained inthe preferred embodiment by Vproviding the flanges With .marginal locking beads 'I3-13 Which 2 l serve to Alock the anges in a transversely stretched or tensioned state Within the closing mold sections V10--10. The mold sections 10 have suitable cavities formed thereprovided with the usual orifice 14 which is formed by lugs projecting from the mold sections', for suspending the bottle in inverted position in the usual manner when not in use.

The closing' and tensioning mold 10 is provided with cavities similar to those in the forming mold for receiving the flanges 12-12, and beads 13-13. It is further provided with a pin 15 for mounting the .tab thereon. In this tensioning mold however the cavities for receivi'ng'the, fianges 12-12 are somewhat wider than the flanges themselves so that when the beads 13--13 are forced into their respective cavities the necessary stretch.. will be produced in the a-l ready-vulcanized rubber f composing the flanges. Likewise the pin" 15 fis farther spaced from the supportingr walls 11-11 than is the orifice 14 from the walls about the slot, thereby producing a corresponding stretch in the tab when mounting it lupon the pin 15. The stretch in lthe rubber composing the tab and fianges Serves to pull and hold the base .of the bottle firmly and continually against the supporting walls 11.

In forming the slot 9,4.it must be of suf- 17, the latter forming a thin layer of rubber Y Vficient length to permit the withdrawal of the core therethrough. lThe slot need not be as long as the width of the core by any means for the vulcanized rubber about the slot will obviously permit of stretching to a considerable extent to facilitate the withdrawal of the core. In this connection however the elasticity of the vulcanized rubber material composing the bottle must be taken into consideration. It is desirable to .produce as small a slot as is feasible and sure in 'the finished product, I preferably Acc continue the flanges 1:2-12 and beads 13-13 for substantial distances beyond the ends of the opening, and as the tongue 6 does not intercept these extending end portions, their opposing faces are consequently brought together, when the mold sections 10 are closed, and are vulcanized .together simul- 'taneously withthe vulcanization of the material composing the body of the bottle. The slot therefore is formed not' only by the margin of the bottle, but also by the opposed flanges and beads, thereby making a very Strong opening yeliminating any danger of tearing the body portion of the bottle when withdrawing the core.

In practising my method, the bottle having been formed and vulcanized in the mold sections 44, it is withdrawn therefrom and thel core removed through the slot. The base ofthe bottle containing the slot is then placed between the closing and tensioning mold sections 10-10 with a strip 16 of vulcanizable rubber inserted between the flanges 12-12 and another strip 17 between the members of the tab 3. The strips may be conveniently circular in cross-section7 Aand the latter strip is preferably put between the tab members in the form of a ring mounted upon the pin 15.

When the mold sections 10--10 are brought together they exert a pressure upon the vulcanized rubber flanges 12-4-12 which has a tendency to flatten them or stretch thenitransversely. This flattening or stretching 'transversely would ordinarily result in .forcing the margins of the bottle away from fthe supporting walls 11-11. 'On account of the flanges 12-12 being previously stretched transversely by the tensioning. mold and vheld in this condition by the locking beads lf3-13 coperating' with the cavities formed in the moldgsections, the above mentioned tendency for displacement of the margins is overcome, and accurate alinement thereof effected.

The pressure produced by the closing mold sections 10-10 and the heat of vulcanization spreads out or flattens the strip 16 and ring .bottleabout the slot, the slot-closing strip of rubber between the flanges will conse-' quently vbe of greater density than that between the sides of the bottle.' And furthermoreas there is no inner supporting wall to prevent, the. closing strip of rubber will fiowor .move V'toward the interior of the bottle and the surplus or over-flow' will emerge density of the portion of the closing strip between these walls.

The bottle in its completed and finally vulcanized condition has a iiash or'in of rubber extending from its joined edges *which represents the over-flow and is usually found in all molded articles.y This i'lash is `finally removed and simultaneously therewith, if desired, the beads 13-13 are also removed. Part of the flanges 12-12 or all of them may be removed if desired. I pre- `fer however to remove only part 'of the flanges and tohave the parts left intact taper from' the tabs toward their ends and to merge at their ends into the margin of the bottle as clearly shown in Fig. 6. This flange materially strengthens the bottle as Vit contains the portion of the closing strip of rubber that has received the greater pressure during the Vulcanizing treatment.

,'Ajsmany apparently Widely differentembodiments of this invention may be, made Without departing from the spirit thereof,

it is to ybe'understood that I do not intend to l limit'myself Ito the specific form of the invention Iasset forth except as indicated in the appended claims. p

shaped at its ends disposed between another portion of said edges and vulcanized thereto simultaneously with the vulcanization of said Fstrip.

2. A Water bottle characterized by having its ymaj or portion including-its side Walls' and 'the major portion of their contacting edges vulcanized simultaneously and a Ifurther portion of elongated shape and having V-shaped end portions vulcanized and vulcanized to the first-mentioned vulcanized portion simultaneously.` Signed at New Haven,

. of J une,v 1918.

JEREMIAH L. MAHONEY.

Conn., this 12 day 

